How is charcoal made?

Carbonization is one of the most important processes in charcoal production. It is not the most expensive, but it requires the most experience. Some people say that the carbonization process is the risk of charcoal production. If you control carbonization, your entire charcoal production process will save a lot of costs and reduce waste of resources.

No matter if you use raw wood to produce charcoal or wooden corner waste to make mechanical charcoal, their raw materials are theoretically wood. If the moisture content of the wood is too high, the charcoal content of the produced charcoal will be low, so it cannot be regarded as good quality charcoal. The main thing we say about charcoal is its charcoal. If the content of charcoal is low, what charcoal is called and what is the value of use, do you think this is the reason? So no matter what method or raw material you use to produce charcoal, it is best to dry the raw material. Dry raw materials are one of the primary guarantees for producing good quality charcoal.

During the entire carbonization process, the wood is maintained at a temperature of about 100 ° C or lower in the carbonization equipment. At this temperature, the moisture in the wood is evaporated until it is zero, and then the burning temperature of the wood is raised to 280 ° C. This step The energy comes from some wood burning heat absorbed by some carbonization equipment, it is an energy absorption or endothermic reaction.

When the wood is dried and heated to about 280 ° C, a pyrolysis reaction occurs, and the wood begins to decompose into charcoal, water vapor, methanol, acetic acid and more complex chemicals, mainly in the form of tar and non-condensable gases composed of hydrogen, carbon monoxide and carbon dioxide. Air is controlled in the kiln during this process, and the oxygen in it is absorbed by the combustion of wood to become carbon dioxide, so there is still nitrogen in the kiln.

The wood continues to burn in the charcoal kiln. This process is called an exothermic reaction. As the exothermic reaction continues, the temperature in the kiln is maintained at about 280 ° C. When it continues to burn, it will leave black lumps in the charcoal kiln. This is charcoal. Due to the low carbonization temperature of the charcoal produced in this way, unless a further external heat source is provided, the maximum temperature in the kiln is about 400 ° C. The fixed carbon content of this charcoal is about 65% -70%, and the ash content is 3-5. %, But it will have a high volatile content. The volatile content of different tree species may be different, but it will generally reach 30%. By further heating, the fixed carbon content of charcoal will increase, and the volatile matter will be decomposed. The temperature in the kiln reaches 500 ° C, the carbon content of charcoal will rise to 85%, and the volatile matter content will drop to about 10%. At this temperature, The charcoal production is about 32% -35% of the weight of the wood. Therefore, the theoretical yield of charcoal varies with temperature, and the volatile tar content in charcoal is also related to the carbonization temperature.

When burning charcoal, the lower the carbonization temperature, the more volatile components of the produced charcoal. As a result, there will be an acidic taste when burning charcoal. This is because charcoal contains a large amount of acidic corrosive tar. This charcoal makes barbecue charcoal, which will change the taste of food, and there will be flames when it is calcined. Good commercial charcoal should be charred at a temperature of about 500 ° C, and about 75% of the fixed carbon.

The production of charcoal is also related to the quality of the raw materials. Good wood has higher lignin content because of its hard wood. In theory, the harder wood is more suitable for producing charcoal, and the harder wood is more suitable for producing charcoal. However, when carbonizing in a charcoal kiln, it is not necessary to put more wood as dense as possible, because if the wood is placed too densely, the wood will be easily broken during carbonization, because the temperature in the kiln rises too quickly and the volatile content decreases. The brittleness of charcoal. Basically, a temperature of 450 ° C to 500 ° C is the best balance between firing charcoal and maintaining a fixed charcoal.

There are many factors that affect the charcoal production and the conversion rate of wood charcoal. Often the charcoal capacity is too low or the waste of raw materials is caused by many factors. Then we try to avoid the factors that may cause problems. Usually we can choose some harder wood as the raw material for charcoal. The firewood should be as dry as possible, and the wood with a diameter of more than 20cm must be split and burned. Otherwise, it is easy to produce charcoal slag and scraps and waste wood materials. When burning charcoal, we must pay attention to the balance of temperature in the charcoal kiln. It is necessary to make the whole kiln reach a carbonization temperature of 500 ° C, but sometimes this is difficult because the irregular air flow in the charcoal kiln causes many raw materials to be burned into charcoal And some are still new. To improve the charring efficiency and quality of charcoal, a well-designed charcoal kiln is very important. A good charcoal kiln not only has good air tightness, but also has a balanced air flow, which does not appear: "cold spots", and the overall temperature in the kiln can quickly rise to a carbonization temperature of 500 ° C.